From 75f32f047cc380bdb648faf3ee277f7dc3cdd007 Mon Sep 17 00:00:00 2001 From: Zbigniew Jędrzejewski-Szmek Date: Mon, 1 Feb 2016 21:57:41 -0500 Subject: Add memcpy_safe MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ISO/IEC 9899:1999 §7.21.1/2 says: Where an argument declared as size_t n specifies the length of the array for a function, n can have the value zero on a call to that function. Unless explicitly stated otherwise in the description of a particular function in this subclause, pointer arguments on such a call shall still have valid values, as described in 7.1.4. In base64_append_width memcpy was called as memcpy(x, NULL, 0). GCC 4.9 started making use of this and assumes This worked fine under -O0, but does something strange under -O3. This patch fixes a bug in base64_append_width(), fixes a possible bug in journal_file_append_entry_internal(), and makes use of the new function to simplify the code in other places. --- src/libsystemd/sd-bus/bus-control.c | 3 +-- src/libsystemd/sd-bus/bus-message.c | 3 +-- src/libsystemd/sd-bus/bus-socket.c | 6 +++--- src/libsystemd/sd-resolve/sd-resolve.c | 5 ++--- 4 files changed, 7 insertions(+), 10 deletions(-) (limited to 'src/libsystemd') diff --git a/src/libsystemd/sd-bus/bus-control.c b/src/libsystemd/sd-bus/bus-control.c index ff628cfe72..00de2a95da 100644 --- a/src/libsystemd/sd-bus/bus-control.c +++ b/src/libsystemd/sd-bus/bus-control.c @@ -1133,8 +1133,7 @@ static int add_name_change_match(sd_bus *bus, item->name_change.old_id.id = old_owner_id; item->name_change.new_id.id = new_owner_id; - if (name) - memcpy(item->name_change.name, name, l); + memcpy_safe(item->name_change.name, name, l); /* If the old name is unset or empty, then * this can match against added names */ diff --git a/src/libsystemd/sd-bus/bus-message.c b/src/libsystemd/sd-bus/bus-message.c index e939359338..6fd0001359 100644 --- a/src/libsystemd/sd-bus/bus-message.c +++ b/src/libsystemd/sd-bus/bus-message.c @@ -2633,8 +2633,7 @@ _public_ int sd_bus_message_append_array( if (r < 0) return r; - if (size > 0) - memcpy(p, ptr, size); + memcpy_safe(p, ptr, size); return 0; } diff --git a/src/libsystemd/sd-bus/bus-socket.c b/src/libsystemd/sd-bus/bus-socket.c index 1df571ac92..4f99719231 100644 --- a/src/libsystemd/sd-bus/bus-socket.c +++ b/src/libsystemd/sd-bus/bus-socket.c @@ -352,7 +352,7 @@ static int bus_socket_auth_write(sd_bus *b, const char *t) { if (!p) return -ENOMEM; - memcpy(p, b->auth_iovec[0].iov_base, b->auth_iovec[0].iov_len); + memcpy_safe(p, b->auth_iovec[0].iov_base, b->auth_iovec[0].iov_len); memcpy(p + b->auth_iovec[0].iov_len, t, l); b->auth_iovec[0].iov_base = p; @@ -789,7 +789,7 @@ int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) { n = m->n_iovec * sizeof(struct iovec); iov = alloca(n); - memcpy(iov, m->iovec, n); + memcpy_safe(iov, m->iovec, n); j = 0; iovec_advance(iov, &j, *idx); @@ -1000,7 +1000,7 @@ int bus_socket_read_message(sd_bus *bus) { return -ENOMEM; } - memcpy(f + bus->n_fds, CMSG_DATA(cmsg), n * sizeof(int)); + memcpy_safe(f + bus->n_fds, CMSG_DATA(cmsg), n * sizeof(int)); bus->fds = f; bus->n_fds += n; } else diff --git a/src/libsystemd/sd-resolve/sd-resolve.c b/src/libsystemd/sd-resolve/sd-resolve.c index d6e6f396d4..c3489cb02f 100644 --- a/src/libsystemd/sd-resolve/sd-resolve.c +++ b/src/libsystemd/sd-resolve/sd-resolve.c @@ -219,9 +219,8 @@ static void *serialize_addrinfo(void *p, const struct addrinfo *ai, size_t *leng memcpy((uint8_t*) p, &s, sizeof(AddrInfoSerialization)); memcpy((uint8_t*) p + sizeof(AddrInfoSerialization), ai->ai_addr, ai->ai_addrlen); - - if (ai->ai_canonname) - memcpy((char*) p + sizeof(AddrInfoSerialization) + ai->ai_addrlen, ai->ai_canonname, cnl); + memcpy_safe((char*) p + sizeof(AddrInfoSerialization) + ai->ai_addrlen, + ai->ai_canonname, cnl); *length += l; return (uint8_t*) p + l; -- cgit v1.2.3-54-g00ecf